Various navigation systems provide users with turn-by-turn directions. These systems may include handheld GPS devices, mobile phones, or vehicle-mounted devices. Users input one or more locations and receive a route and turn-by-turn directions based on the inputted locations. The user may follow the turn-by-turn directions to reach the one or more locations.
These navigation systems rely on the ability to receive information from a plurality of GPS satellites. This allows for identification of a current location of a device for providing navigational assistance. However, while indoors, a mobile device may require accurate localization to enable features such as advanced indoor navigation, for example, to conference rooms in a building or stores within a mall. In an indoor environment, accurate localization is difficult due to the lack of adequate signals from the GPS satellites.
Many modern commercial facilities include numerous wireless network access points which may be used in order to provide indoor localization.